问问为什么python两次切片后的数据无法修改？

Question

我在进行多维数组两次切片操作后，想要修改其中的数据，但是无法修改，这是为什么？

import numpy as np
names = np.array(["张","李","王","赵"])
subjects = np.array(["English","Python","Math"])
scores = np.random.randint(0,6,size = (4,3))
print(scores)
print(scores[(names == "李"),:][:,subjects == "Math"])
scores[(names == "李"),:][:,subjects == "Math"] = scores[(names == "李"),:][:,subjects == "Math"] - 2
print(scores[(names == "李"),:][:,subjects == "Math"])
print(scores)

附上某一次的运行结果

Answer 1

切片会产生新对象，你用一个新对象接收并赋值即可。